I have also used the Howards EDM lifters with good results. Before EDM lifters were available I had a tool that would cut a small groove in the lifter bore which increased the oiling to the lifter, that worked as well, just took some time to cut the grooves. Much quicker to use the EDM lifter after they came out. Anything much over .600 lift I use a roller lifter, due to the spring pressure needed on higher lift cams.
